diff --git a/cmd/cue/cmd/mod.go b/cmd/cue/cmd/mod.go
new file mode 100644
index 0000000..5e356f1
--- /dev/null
+++ b/cmd/cue/cmd/mod.go
@@ -0,0 +1,175 @@
+// Copyright 2019 CUE Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cmd
+
+import (
+	"fmt"
+	"math/rand"
+	"net/url"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/spf13/cobra"
+)
+
+func newModCmd(c *Command) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "mod <cmd> [arguments]",
+		Short: "module maintenace",
+		Long: `
+`,
+		RunE: mkRunE(c, func(cmd *Command, args []string) error {
+			stderr := cmd.Stderr()
+			if len(args) == 0 {
+				fmt.Fprintln(stderr, "mod must be run as one of its subcommands")
+			} else {
+				fmt.Fprintf(stderr, "get must be run as one of its subcommands: unknown subcommand %q\n", args[0])
+			}
+			fmt.Fprintln(stderr, "Run 'cue help mod' for known subcommands.")
+			os.Exit(1) // TODO: get rid of this
+			return nil
+		}),
+	}
+
+	cmd.AddCommand(newModInitCmd(c))
+	return cmd
+}
+
+func newModInitCmd(c *Command) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "init [module]",
+		Short: "initialize new module in current director",
+		Long: `Init initializes a cue.mod directory in the current directory,
+in effect creating a new module rooted at the current directory.
+The cue.mod directory must not already exist.
+A legacy cue.mod file in the current directory is moved
+to the new subdirectory.
+
+A module name is optional, but if it is not given a packages
+within the module cannot imported another package defined
+in the module.
+`,
+		RunE: mkRunE(c, runModInit),
+	}
+
+	cmd.Flags().BoolP(string(flagForce), "f", false, "force moving old-style cue.mod file")
+
+	return cmd
+}
+
+func runModInit(cmd *Command, args []string) (err error) {
+	defer func() {
+		if err != nil {
+			// TODO: Refactor Cobra usage to do something more principled
+			fmt.Fprintln(cmd.OutOrStderr(), err)
+			os.Exit(1)
+		}
+	}()
+
+	module := ""
+	if len(args) > 0 {
+		if len(args) != 1 {
+			return fmt.Errorf("too many arguments")
+		}
+		module := args[0]
+		u, err := url.Parse("https://" + module)
+		if err != nil {
+			return fmt.Errorf("invalid module name: %v", module)
+		}
+		if h := u.Hostname(); !strings.Contains(h, ".") {
+			return fmt.Errorf("invalid host name %q", h)
+		}
+	}
+
+	cwd, err := os.Getwd()
+	if err != nil {
+		return err
+	}
+
+	mod := filepath.Join(cwd, "cue.mod")
+
+	info, err := os.Stat(mod)
+
+	// Detect old setups and backport it if requested.
+	if err == nil && !info.IsDir() {
+		// This path backports
+		if !flagForce.Bool(cmd) {
+			return fmt.Errorf("detected old-style config file; use --force to upgrade")
+		}
+		return backport(mod, cwd)
+	}
+
+	if err == nil {
+		return fmt.Errorf("cue.mod directory already exists")
+	}
+
+	err = os.Mkdir(mod, 0755)
+	if err != nil && !os.IsExist(err) {
+		return err
+	}
+
+	f, err := os.Create(filepath.Join(mod, "module.cue"))
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	// Set module even if it is empty, making it easier for users to fill it in.
+	_, err = fmt.Fprintf(f, "module: %q\n", module)
+
+	if err = os.Mkdir(filepath.Join(mod, "usr"), 0755); err != nil {
+		return err
+	}
+	if err = os.Mkdir(filepath.Join(mod, "pkg"), 0755); err != nil {
+		return err
+	}
+
+	return err
+}
+
+// backport backports an old cue.mod setup to a new one.
+func backport(mod, cwd string) error {
+	tmp := filepath.Join(cwd, fmt.Sprintf("_%x_cue.mod", rand.Int()))
+	err := os.Rename(mod, tmp)
+	if err != nil {
+		return err
+	}
+
+	err = os.Mkdir(filepath.Join(cwd, "cue.mod"), 0755)
+	if err != nil {
+		os.Rename(tmp, mod)
+		return err
+	}
+
+	err = os.Rename(tmp, filepath.Join(cwd, "cue.mod", "module.cue"))
+	if err != nil {
+		return err
+	}
+
+	err = os.Rename(filepath.Join(cwd, "pkg"), filepath.Join(cwd, "cue.mod", "gen"))
+	if err != nil && !os.IsNotExist(err) {
+		return err
+	}
+
+	if err = os.Mkdir(filepath.Join(mod, "usr"), 0755); err != nil {
+		return err
+	}
+	if err = os.Mkdir(filepath.Join(mod, "pkg"), 0755); err != nil {
+		return err
+	}
+
+	return nil
+}
diff --git a/cmd/cue/cmd/root.go b/cmd/cue/cmd/root.go
index 6fcc8ce..75e8e58 100644
--- a/cmd/cue/cmd/root.go
+++ b/cmd/cue/cmd/root.go
@@ -81,15 +81,18 @@
 	c.cmd = cmdCmd
 
 	subCommands := []*cobra.Command{
-		newTrimCmd(c),
-		newImportCmd(c),
-		newEvalCmd(c),
-		newGetCmd(c),
-		newFmtCmd(c),
-		newExportCmd(c),
 		cmdCmd,
+		newEvalCmd(c),
+		newExportCmd(c),
+		newFmtCmd(c),
+		newGetCmd(c),
+		newImportCmd(c),
+		newModCmd(c),
+		newTrimCmd(c),
 		newVersionCmd(c),
 		newVetCmd(c),
+
+		// Hidden
 		newAddCmd(c),
 	}